Hi Mike,
Check out the following:
http://www.datasprings.com/news/blog/postid/7 You will find that you need to utilize the right setting(s) in the Dynamic Forms > Module Configuration > Payment Gateway > PayPal Gateway and the information in the blog should direct you along the right path.
PayPal is a complex process and we have a support analyst that is expert in setting up this for you if you find that you are stuck. If you choose this option then through our premium support option we can help you.
Please look at:
https://www.datasprings.com/Support/ProductSupportAgreement/PremiumSupportOptions/PremiumHourlySupport/tabid/879/language/en-US/Default.aspx
Thanks